1. Field of the Invention
The present invention relates to a vectorial network analyzer (VNA) having at least one signal generator which generates a particular RF output signal, and having n measuring ports, where n is an integer greater than or equal to one, wherein an RF coupler is assigned to each measuring port and the RF coupler is designed in such a manner that the RF coupler couples out an RF signal bn running into the particular port from the outside, wherein the at least one signal generator is arranged and designed in such a manner that the latter supplies a particular RF output signal to at least one measuring port as an RF signal an running out to the outside.
The invention also relates to a method for determining scattering parameters of an electronic device under test, wherein at least one electromagnetic wave an running into the device under test and at least one electromagnetic wave bn propagated from the device under test are determined and scattering parameters of the device under test are calculated in terms of amount and/or phase from the determined waves an and bn, wherein the at least one electromagnetic wave bn propagated from the device under test is measured by means of an RF coupler, and wherein the at least one electromagnetic wave an running into the device under test is generated by at least one signal generator.
2. Description of Related Art
In the field of electronics, vectorial network analyzers (VNA) have for many years been used for the precise measurement of electronic linear components and components of active and passive circuits or assemblies at low frequencies (as LCR meters) and in the high frequency range into the THz range as well as the optical range. A VNA records the scattering parameters of n-port networks (n=1, 2, . . . ), which may be converted into 2n-pole parameters (e.g. Z- or Y-parameters). However, in the case of mid- and high-frequencies in particular (fast circuits, i.e., circuits in the MHz and GHz range), these recorded measured data display very high measuring errors. Nowadays, these measuring errors have also been immensely reduced in almost every NF device (LCR meters) by means of mathematical methods. An associated systematic error correction in the VNAs ensures that precise measurements of fast electronic components, i.e., components in the MHz and GHz range, with exclusively linear transmission behavior can be carried out at all.
The measuring accuracy of VNAs depends primarily on the availability of a method for systematic error correction and the associated calibration standard. In systematic error correction, within the so-called calibration procedure the reflection and/or transmission behavior of devices under test which are partially or wholly known are measured. Correction data (so-called error factors or coefficients) are obtained from these measured data using special calculation methods. With these correction data and a corresponding correction calculation, measured data can be obtained for any given device under test which are free of systematic errors in the VNA and the input lines (miscoupling=crosstalk, mismatches=reflections).
The usual form of describing the electrical behavior of components and circuits in high frequency technology (RF technology) is by means of the scattering parameters (also referred to as S-parameters). The scattering parameters interrelate not currents and voltages but wave characteristics. This form of representation is particularly well adapted to the physical conditions of RF technology. If necessary, these scattering parameters can be converted into other electrical network parameters which interrelate currents and voltages.